Field of the Disclosure
The present disclosure, for example, relates to wireless communication systems, and more particularly to techniques for robust and low latency uplink acknowledgement channel design.
Description of Related Art
Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be multiple-access systems capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code-division multiple access (CDMA) systems, time-division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, and orthogonal frequency-division multiple access (OFDMA) systems.
By way of example, a wireless multiple-access communication system may include a number of base stations, each simultaneously supporting communication for multiple communication devices, otherwise known as user equipments (UEs). A base station may communicate with UEs on downlink channels (e.g., for transmissions from a base station to a UE) and uplink channels (e.g., for transmissions from a UE to a base station).
Wireless communication systems often utilize retransmission procedures to provide error detect and correct functionality. For example, a receiving device (a UE or base station) may receive a transmission, confirm that a transport block is decoded without errors, and then send an acknowledgement (ACK) message to the sending device (a base station or UE) confirming successful decoding of the transport block. If errors are detected, the receiving device sends a negative-acknowledgement (NACK) to the sending device, which initiates a retransmission procedure. The ACK/NACK messages are typically sent via a dedicated channel from the receiving device to the transmitting device, e.g., via a physical hybrid automatic repeat request (HARM) indicator channel (PHICH), a physical uplink control channel (PUCCH), etc. Conventional communication systems may not consider latency issues when communicating the ACK/NACK information and may not provide for robustness in the ACK/NACK transmissions.